Sanborn Fire Insurance Maps (Search for Towns in Pennsylvania, via Penn State University) – “The Sanborn Map Company, the best known of the US fire-insurance map producers, has made maps since 1867. The fire insurance maps produced by Sanborn show building footprints, building material, height or number of stories, building use, lot lines, road widths and water facilities. The maps also show street names and property boundaries of the time. This collection of maps is historically significant as it is sometimes the best detailed map of a town or city dating from the mid-1800s.”